A mixer with obsolet articles to get a new one and then rewrite.
There's a website to do some thing like that. I don't remember right noe.
This feature already exists – sort of. Go to TOOLS/ARTICLE FINDER and select LOCAL from the source box. You can set the local search path in ADVANCED OPTIONS.
This will allow you to search local articles and manually merge them.
We have an automatic article mixer in road map.